Lowbank

Active Member
I have taken a number of readings on my two TD4 , a 52 plate and a 54 plate.
Think the MAP is cream crackered on the 52 plate and the airflow is an issue on the 54 plate.

Any ideas welcomed.
readings will be on next post as picture is on my phone.
 
image.jpeg
 
So after a very short search on the 52 plate. The MAP was disconnected. Reconnected and readings normal.
 
52 plate MAP is well out. It should show 100 Kpa at idle.
54 plate MAF isn't working correctly.
HP and LP pressures look ok.
The 52 plate isn't running hot enough either;)
 
Brill idea to compare 2 cars readings. How about we put together a set of readings for a 'correct' car and then some notes to help fault-find when out of spec??

This site is the place to inject readings from every fault known to man...........

I have an Icarsoft and happy to log what my car looks like, but I wouldn't guarantee that it is 'correct' !
 
Thanks Nodge,
I am going to read a 55 plate TD4 tomorrow as well to compare.

The. 52 plate was just idling on the drive and I got fed up waiting for it. to go higher.

I have another MAF, not sure if its the same so will check and perhaps try fitting it tomorrow and read it again.

I think its a good idea to have sticky thread of Good readings at different settings.

I am collecting a full set of spare sensors so I help people who are close.
 
Just taken a set of readings on my (appears to be o.k) TD4 2002 134k miles. Three different temperatures as it warms up, but not fully warm. Another at around 2k RPM.
upload_2016-12-13_14-26-40.png
upload_2016-12-13_14-26-40.png


Also noted that mine has a P0404 fault code. This shows as an EGR out of spec fault. The EGR has been bypassed for a long time and not seen this fault code before! Any ideas??
Moderators - can we put a document up like this for all to add to?? Also, I'll work up a definitions of terms page. Thanks
 
pretty please moderators.
I did a 55 plate this weekend which was running really well, will post results later. Hp was lower than my two and so was airflow.
 
We also need to work up what reading comes from where, as I think I am nearly there but no idea what the capacitor reading id for or where it taken from.
 
Good stuff. What is the MAS (mine hasn't got that on the options)?
I'm trying to find out what capacitor is.
Also, which cars of yours have EGR By-pass and which don't please?
All my entries the cars have bypass. One shows a P0404 fault and the other doesn't !!
 
The MAS reading was taken by selecting the second down option at the start menu, OBDll diagnose,it selects ISo9141, press ok
Then select data stream,
Then view all items.
does not work on the 52 plate just tried
at tick over pedal 1 demand. 0.77% pedal 2 0.39% sensor supply both 5.01v
 
Apparantly the capacitor is inside the ECU and should be showing around 0.80v when the car is running.
 
View attachment 112907 Did not want to wait any longer for it to warm up the 55 plate that is.

Is the MAP sensor blocked on the 52 plate car? The MAP should show 100 Kpa when not boosting. 100 is atmospheric pressure. Anything under atmospheric at idle would suggest a blocked or faulty sensor. Or a very coked up inlet manifold. Anything under 100 Kpa with the engine off would suggest a blocked or faulty sensor.

I'm trying to find out what capacitor is.
The capacitor is what fires the piezo elements in the injectors;)
It should be around 80 Volts when the injectors are firing.
 
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Hi Nodge68,
I did a search in the engine bay the other day and the connector had fallen of the MAP, reconnected now and showing 100.0 when engine is off. Car is running a lot better.
My 54 plate is still running like a dog.
Flat spots on gear change and low power, doing 400 miles to a full tank of fuel.
I have a spare MAF, just need time to fit and see if that helps.
 
Hi Nodge68,
I did a search in the engine bay the other day and the connector had fallen of the MAP, reconnected now and showing 100.0 when engine is off. Car is running a lot better.
My 54 plate is still running like a dog.
Flat spots on gear change and low power, doing 400 miles to a full tank of fuel.
I have a spare MAF, just need time to fit and see if that helps.

Glad you sorted out the MAP signal. It will run better when it knows how much fuel to put in;)

The MAF signal is all wrong on the 54 plate car. Definitely worth changing the MAF.
 
Someone has suggested there maybe a leak in the system.
Only pipe I havn't changed is the one at the back of the engine.
IMG_0233.JPG
 
Didnt have time to remove the MAF today but did get time to unplug it.

Car runs lots better, will take some readings tomorrow so I know what default ecu readings are.
 

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